Mastering SQL Query Basics

What does SQL stand for?

• Simple Query Language

• Standard Query Language

• Structured Query Language

• Structured Query List

Which SQL statement is used to retrieve data from a database?

• DELETE

• SELECT

• UPDATE

• INSERT

How do you select all columns from a table named 'employees'?

• SELECT * FROM employees;

• GET * FROM employees;

• FETCH * FROM employees;

• SELECT ALL FROM employees;

What is the purpose of the WHERE clause in SQL?

• To sort records in ascending order.

• To create new database records.

• To filter records based on specified conditions.

• To join multiple tables together.

Which SQL keyword is used to sort the result set?

• ORDER BY

• SELECT

• GROUP BY

• FILTER

How do you insert a new record into a table named 'products'?

• INSERT INTO products (column1, column2) VALUES (value1, value2);

• SELECT * FROM products WHERE column1 = value1;

• DELETE FROM products WHERE condition;

• UPDATE products SET column1 = value1 WHERE condition;

What is the function of the GROUP BY clause in SQL?

• To join multiple tables into a single result set.

• To filter rows based on a specific condition.

• To group rows that have the same values in specified columns and perform aggregate functions on them.

• To sort rows in ascending or descending order.

How can you update existing records in a table?

• Use the SQL UPDATE statement with SET and WHERE clauses.

• Use the SQL SELECT statement to retrieve records.

• Delete the records and reinsert them with new values.

• Use the SQL INSERT statement to add new records.

What SQL statement is used to delete records from a table?

• REMOVE FROM table_name WHERE condition;

• DROP table_name WHERE condition;

• DELETE FROM table_name WHERE condition;

• CLEAR FROM table_name WHERE condition;

What is the difference between INNER JOIN and LEFT JOIN?

• INNER JOIN returns matched rows only; LEFT JOIN returns all rows from the left table and matched rows from the right.

• INNER JOIN includes unmatched rows from both tables; LEFT JOIN excludes unmatched rows from the left table.

• INNER JOIN returns all rows from both tables; LEFT JOIN returns only unmatched rows from the left table.

• INNER JOIN returns all rows from the left table; LEFT JOIN returns only matched rows from the right table.